_content/doc: fix inconsistent tabs in code snippets

Replace real tabs with 4 spaces in code snippets to make indentation
consistent

Fixes golang/go#52255

Change-Id: Ida06a1dd2c2cd3100c32d6c29febf60aba2e20d7
Reviewed-on: https://go-review.googlesource.com/c/website/+/399374
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Jamal Carvalho <jamal@golang.org>
diff --git a/_content/doc/articles/wiki/index.html b/_content/doc/articles/wiki/index.html
index 107fba4..b88a820 100644
--- a/_content/doc/articles/wiki/index.html
+++ b/_content/doc/articles/wiki/index.html
@@ -54,8 +54,8 @@
 package main
 
 import (
-	"fmt"
-	"os"
+    "fmt"
+    "os"
 )
 </pre>
 
@@ -255,10 +255,10 @@
 
 <pre>
 import (
-	"fmt"
-	"os"
-	"log"
-	<b>"net/http"</b>
+    "fmt"
+    "os"
+    "log"
+    <b>"net/http"</b>
 )
 </pre>
 
@@ -371,9 +371,9 @@
 
 <pre>
 import (
-	<b>"html/template"</b>
-	"os"
-	"net/http"
+    <b>"html/template"</b>
+    "os"
+    "net/http"
 )
 </pre>
 
@@ -649,10 +649,10 @@
 
 <pre>
 func makeHandler(fn func (http.ResponseWriter, *http.Request, string)) http.HandlerFunc {
-	return func(w http.ResponseWriter, r *http.Request) {
-		// Here we will extract the page title from the Request,
-		// and call the provided handler 'fn'
-	}
+    return func(w http.ResponseWriter, r *http.Request) {
+        // Here we will extract the page title from the Request,
+        // and call the provided handler 'fn'
+    }
 }
 </pre>
 
diff --git a/_content/doc/code.html b/_content/doc/code.html
index 35b7c19..1219cf3 100644
--- a/_content/doc/code.html
+++ b/_content/doc/code.html
@@ -99,7 +99,7 @@
 import "fmt"
 
 func main() {
-	fmt.Println("Hello, world.")
+    fmt.Println("Hello, world.")
 }
 </pre>
 
@@ -230,11 +230,11 @@
 
 // ReverseRunes returns its argument string reversed rune-wise left to right.
 func ReverseRunes(s string) string {
-	r := []rune(s)
-	for i, j := 0, len(r)-1; i &lt; len(r)/2; i, j = i+1, j-1 {
-		r[i], r[j] = r[j], r[i]
-	}
-	return string(r)
+    r := []rune(s)
+    for i, j := 0, len(r)-1; i &lt; len(r)/2; i, j = i+1, j-1 {
+        r[i], r[j] = r[j], r[i]
+    }
+    return string(r)
 }
 </pre>
 
@@ -270,13 +270,13 @@
 package main
 
 import (
-	"fmt"
+    "fmt"
 
-	<b>"example/user/hello/morestrings"</b>
+    <b>"example/user/hello/morestrings"</b>
 )
 
 func main() {
-	fmt.Println(morestrings.ReverseRunes("!oG ,olleH"))
+    fmt.Println(morestrings.ReverseRunes("!oG ,olleH"))
 }
 </pre>
 
@@ -310,15 +310,15 @@
 package main
 
 import (
-	"fmt"
+    "fmt"
 
-	"example/user/hello/morestrings"
-	"github.com/google/go-cmp/cmp"
+    "example/user/hello/morestrings"
+    "github.com/google/go-cmp/cmp"
 )
 
 func main() {
-	fmt.Println(morestrings.ReverseRunes("!oG ,olleH"))
-	fmt.Println(cmp.Diff("Hello World", "Hello Go"))
+    fmt.Println(morestrings.ReverseRunes("!oG ,olleH"))
+    fmt.Println(cmp.Diff("Hello World", "Hello Go"))
 }
 </pre>
 
@@ -337,8 +337,8 @@
 $ hello
 Hello, Go!
   string(
-- 	"Hello World",
-+ 	"Hello Go",
+-     "Hello World",
++     "Hello Go",
   )
 $ cat go.mod
 module example/user/hello
@@ -392,19 +392,19 @@
 import "testing"
 
 func TestReverseRunes(t *testing.T) {
-	cases := []struct {
-		in, want string
-	}{
-		{"Hello, world", "dlrow ,olleH"},
-		{"Hello, 世界", "界世 ,olleH"},
-		{"", ""},
-	}
-	for _, c := range cases {
-		got := ReverseRunes(c.in)
-		if got != c.want {
-			t.Errorf("ReverseRunes(%q) == %q, want %q", c.in, got, c.want)
-		}
-	}
+    cases := []struct {
+        in, want string
+    }{
+        {"Hello, world", "dlrow ,olleH"},
+        {"Hello, 世界", "界世 ,olleH"},
+        {"", ""},
+    }
+    for _, c := range cases {
+        got := ReverseRunes(c.in)
+        if got != c.want {
+            t.Errorf("ReverseRunes(%q) == %q, want %q", c.in, got, c.want)
+        }
+    }
 }
 </pre>
 
diff --git a/_content/doc/effective_go.html b/_content/doc/effective_go.html
index 6104d3a..632a808 100644
--- a/_content/doc/effective_go.html
+++ b/_content/doc/effective_go.html
@@ -815,27 +815,27 @@
 
 <pre>
 Loop:
-	for n := 0; n &lt; len(src); n += size {
-		switch {
-		case src[n] &lt; sizeOne:
-			if validateOnly {
-				break
-			}
-			size = 1
-			update(src[n])
+    for n := 0; n &lt; len(src); n += size {
+        switch {
+        case src[n] &lt; sizeOne:
+            if validateOnly {
+                break
+            }
+            size = 1
+            update(src[n])
 
-		case src[n] &lt; sizeTwo:
-			if n+1 &gt;= len(src) {
-				err = errShortInput
-				break Loop
-			}
-			if validateOnly {
-				break
-			}
-			size = 2
-			update(src[n] + src[n+1]&lt;&lt;shift)
-		}
-	}
+        case src[n] &lt; sizeTwo:
+            if n+1 &gt;= len(src) {
+                err = errShortInput
+                break Loop
+            }
+            if validateOnly {
+                break
+            }
+            size = 2
+            update(src[n] + src[n+1]&lt;&lt;shift)
+        }
+    }
 </pre>
 
 <p>
@@ -1490,9 +1490,9 @@
 
 <pre>
 text := LinesOfText{
-	[]byte("Now is the time"),
-	[]byte("for all good gophers"),
-	[]byte("to bring some fun to the party."),
+    []byte("Now is the time"),
+    []byte("for all good gophers"),
+    []byte("to bring some fun to the party."),
 }
 </pre>
 
@@ -1515,7 +1515,7 @@
 picture := make([][]uint8, YSize) // One row per unit of y.
 // Loop over the rows, allocating the slice for each row.
 for i := range picture {
-	picture[i] = make([]uint8, XSize)
+    picture[i] = make([]uint8, XSize)
 }
 </pre>
 
@@ -1530,7 +1530,7 @@
 pixels := make([]uint8, XSize*YSize) // Has type []uint8 even though picture is [][]uint8.
 // Loop over the rows, slicing each row from the front of the remaining pixels slice.
 for i := range picture {
-	picture[i], pixels = pixels[:XSize], pixels[XSize:]
+    picture[i], pixels = pixels[:XSize], pixels[XSize:]
 }
 </pre>
 
@@ -2520,7 +2520,7 @@
 
 <pre>
 if _, err := os.Stat(path); os.IsNotExist(err) {
-	fmt.Printf("%s does not exist\n", path)
+    fmt.Printf("%s does not exist\n", path)
 }
 </pre>
 
diff --git a/_content/doc/faq.html b/_content/doc/faq.html
index 1a0d4c4..8239e51 100644
--- a/_content/doc/faq.html
+++ b/_content/doc/faq.html
@@ -966,11 +966,11 @@
 
 <pre>
 func returnsError() error {
-	var p *MyError = nil
-	if bad() {
-		p = ErrBad
-	}
-	return p // Will always return a non-nil error.
+    var p *MyError = nil
+    if bad() {
+        p = ErrBad
+    }
+    return p // Will always return a non-nil error.
 }
 </pre>
 
@@ -987,10 +987,10 @@
 
 <pre>
 func returnsError() error {
-	if bad() {
-		return ErrBad
-	}
-	return nil
+    if bad() {
+        return ErrBad
+    }
+    return nil
 }
 </pre>
 
@@ -1060,7 +1060,7 @@
 
 <pre>
 type Copyable interface {
-	Copy() interface{}
+    Copy() interface{}
 }
 </pre>
 
@@ -2096,7 +2096,7 @@
 type S[T any] struct { f T }
 
 func (s S[string]) Add(t string) string {
-	return s.f + t
+    return s.f + t
 }
 </pre>
 
diff --git a/_content/ref/mod.md b/_content/ref/mod.md
index dd4ebc5..13db401 100644
--- a/_content/ref/mod.md
+++ b/_content/ref/mod.md
@@ -788,8 +788,8 @@
 
 ```
 retract (
-	v1.0.0 // Published accidentally.
-	v1.0.1 // Contains retractions only.
+    v1.0.0 // Published accidentally.
+    v1.0.1 // Contains retractions only.
 )
 ```
 
@@ -1941,33 +1941,33 @@
 
 ```
 type Module struct {
-        Path    string
-        Version string
+    Path    string
+    Version string
 }
 
 type GoMod struct {
-        Module  Module
-        Go      string
-        Require []Require
-        Exclude []Module
-        Replace []Replace
+    Module  Module
+    Go      string
+    Require []Require
+    Exclude []Module
+    Replace []Replace
 }
 
 type Require struct {
-        Path     string
-        Version  string
-        Indirect bool
+    Path     string
+    Version  string
+    Indirect bool
 }
 
 type Replace struct {
-        Old Module
-        New Module
+    Old Module
+    New Module
 }
 
 type Retract struct {
-        Low       string
-        High      string
-        Rationale string
+    Low       string
+    High      string
+    Rationale string
 }
 
 ```
@@ -2820,9 +2820,9 @@
 go 1.12
 
 require (
-	golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550
-	golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e
-	golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898
+    golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550
+    golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e
+    golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898
 )
 ```
 
@@ -4563,4 +4563,4 @@
 <a id="glos-workspace"></a>
 **workspace:** A collection of modules on disk that are used as
 the root modules when running [minimal version selection (MVS)](#minimal-version-selection).
-See the section on [Workspaces](#workspaces)
\ No newline at end of file
+See the section on [Workspaces](#workspaces)